The present invention relates to a cargo handling system for transporting and handling of cargo and to a cargo container for use in the cargo handling system.
Various types of cargo containers are commonly used. Among such containers relatively small sized containers are mainly used for sorting and storage of cargo in a warehouse. Some of such small sized containers have wheels on their bottoms for short distance movement by hand (human power), rather than a forklift truck. In the case of containers to be loaded on a truck or trailer, wheels fixed to the bottom, with bolts; and nuts or by other known means, present the following problems:
(1) Due to the height of the wheels on the bottom, some space is killed where such wheeled containers are stored, e.g., in a storage rack, a large sized container or a truck. PA1 (2) The wheels on the bottom reduce stability of the container itself in a storage area or a transportation vehicle. PA1 (3) The wheels on the bottom may be an obstacle to compatibility with other systems, equipment or facilities that may accept these containers. Containers with wheels fixed to their bottom walls are apt to be unstable in a storage rack or a display stand, for example, which may lead to unexpected movement therein. PA1 1. The height of such containers exceeds aircraft cargo compartments in most cases. PA1 2. Only "air cargo containers" that meet particular technical requirements are used for air transportation. PA1 3. The incompatibility between "air cargo containers" and other containers has not been solved.
Because of such problems, use of cargo containers with wheels fixed to their bottoms may necessitate piece-by-piece transfer of cargo to another container that better serves the purpose. Piece-by-piece transfer of cargo to another container not only requires much time and human resources but can also cause damage to cargo packages. The expenses of piece-by-piece transfer and packaging for protection against damage result in a high cost for transportation of cargo.
Cargo shipments to be carried by air must be transported to an airport or airport-related facility for preparation for airlift. Transportation of air cargo to such facilities is done by truck in most cases, and cargoes are loaded in trucks loose or packed in various types of containers. Cargoes are then carried to an airport or airport-related facility where they are unloaded from trucks or containers piece-by-piece and then put in "air cargo containers," again piece by piece, because containers used for transportation by truck can not be fitted to an air carriage for the following reasons: